Judge Mr Justice Baker thanked the jury, and added: "It is never easy in a case like this."

Throughout his three-week trial, father-of-one Pearce denied murder and manslaughter.

He said he did not do anything to hurt Alfie, who he killed at his home in August 2013.

Ms Sullock had left Alfie, born on 6 July 2013, with Pearce, who she was in a relationship with at the time, to enjoy her first night out since giving birth.

The pair had become friends while she was six months pregnant, and later became a couple.

Although the court was told Pearce began to display "obsessive behaviour" towards Ms Sullock - and even asked her to give him a child just weeks into their relationship.

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Pearce claimed he did not hurt Alfie and gave him mouth-to-mouth resuscitation

'Trust me'

On 16 August, Ms Sullock travelled from her home in Cardiff to Pearce's house in Nelson, Caerphilly county, to stay the weekend. Pearce suggested she go out with his friend's girlfriend for a "girly night out".

That night Pearce had drunk five pints of beer - four of them in 45 minutes.

He then returned home and looked after Alfie while Ms Sullock got ready.

She told the court her baby was fine when she left Pearce's house.

But less than half-an-hour into her night out, the pair exchanged a series of text messages.

Pearce maintained Alfie was fine but shortly after he sent a text saying, "you can trust me" he dialled 999 and called Ms Sullock to say Alfie had stopped breathing and was being taken to Prince Charles Hospital.

Alfie was transferred to the University Hospital of Wales, Cardiff, where four days later - on 20 August - life support was withdrawn and he died.

A post mortem examination showed Alfie died of blunt trauma injury and extensive bleeding into the brain.

After deliberating for 35 hours and 56 minutes, the jury decided by a majority verdict of 10-2 that Pearce was guilty of manslaughter but cleared him of murder.

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Donna Sullock was enjoying her first night out since Alfie's birth when he was battered by Pearce